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Printed, Flexible and Rechargeable Battery Can Power Wearable Sensors

Nanoengineers at the University of California San Diego have developed the first printed battery that is flexible, stretchable and rechargeable. The zinc batteries could be used to power everything from wearable sensors to solar cells and other kinds of electronics. The work appears in the April 19, 2017 issue of Advanced Energy Materials.

Neutrons Provide the First Nanoscale Look at a Living Cell Membrane

A research team from the Department of Energy's Oak Ridge National Laboratory has performed the first-ever direct nanoscale examination of a living cell membrane. In doing so, it also resolved a long-standing debate by identifying tiny groupings of lipid molecules that are likely key to the cell's functioning.

How X-Rays Helped to Solve Mystery of Floating Rocks

Experiments at Berkeley Lab's Advanced Light Source have helped scientists to solve a mystery of why some rocks can float for years in the ocean, traveling thousands of miles before sinking.

Special X-Ray Technique Allows Scientists to See 3-D Deformations

In a new study published last Friday in Science, researchers at Argonne used an X-ray scattering technique called Bragg coherent diffraction imaging to reconstruct in 3-D the size and shape of grain defects. These defects create imperfections in the lattice of atoms inside a grain that can give rise to interesting material properties and effects.

Neptune: Neutralizer-Free Plasma Propulsion

The most established plasma propulsion concepts are gridded-ion thrusters that accelerate and emit a larger number of positively charged particles than those that are negatively charged. To enable the spacecraft to remain charge-neutral, a "neutralizer" is used to inject electrons to exactly balance the positive ion charge in the exhaust beam. However, the neutralizer requires additional power from the spacecraft and increases the size and weight of the propulsion system. Researchers are investigating how the radio-frequency self-bias effect can be used to remove the neutralizer altogether, and they report their work in this week's Physics of Plasmas.

Report Sheds New Insights on the Spin Dynamics of a Material Candidate for Low-Power Devices

In a report published in Nano LettersArgonne researchers reveal new insights into the properties of a magnetic insulator that is a candidate for low-power device applications; their insights form early stepping-stones towards developing high-speed, low-power electronics that use electron spin rather than charge to carry information.

Researchers Find Computer Code That Volkswagen Used to Cheat Emissions Tests

An international team of researchers has uncovered the mechanism that allowed Volkswagen to circumvent U.S. and European emission tests over at least six years before the Environmental Protection Agency put the company on notice in 2015 for violating the Clean Air Act. During a year-long investigation, researchers found code that allowed a car's onboard computer to determine that the vehicle was undergoing an emissions test.

Physicists Discover That Lithium Oxide on Tokamak Walls Can Improve Plasma Performance

A team of physicists has found that a coating of lithium oxide on the inside of fusion machines known as tokamaks can absorb as much deuterium as pure lithium can.

Scientists Perform First Basic Physics Simulation of Spontaneous Transition of the Edge of Fusion Plasma to Crucial High-Confinement Mode

PPPL physicists have simulated the spontaneous transition of turbulence at the edge of a fusion plasma to the high-confinement mode that sustains fusion reactions. The research was achieved with the extreme-scale plasma turbulence code XGC developed at PPPL in collaboration with a nationwide team.

Green Fleet Technology

New research at Penn State addresses the impact delivery trucks have on the environment by providing green solutions that keep costs down without sacrificing efficiency.


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Rensselaer Polytechnic Institute Graduates Urged to Embrace Change at 211th Commencement

Describing the dizzying pace of technological innovation, former United States Secretary of Energy Ernest J. Moniz urged graduates to "anticipate career change, welcome it, and manage it to your and your society's benefit" at the 211th Commencement at Rensselaer Polytechnic Institute (RPI) Saturday.

ORNL Welcomes Innovation Crossroads Entrepreneurial Research Fellows

Oak Ridge National Laboratory today welcomed the first cohort of innovators to join Innovation Crossroads, the Southeast region's first entrepreneurial research and development program based at a U.S. Department of Energy national laboratory.

Department of Energy Secretary Recognizes Argonne Scientists' Work to Fight Ebola, Cancer

Two groups of researchers at Argonne earned special awards from the office of the U.S. Secretary of Energy for addressing the global health challenges of Ebola and cancer.

Jefferson Science Associates, LLC Recognized for Leadership in Small Business Utilization

Jefferson Lab/Jefferson Science Associates has a long-standing commitment to doing business with and mentoring small businesses. That commitment and support received national recognition at the 16th Annual Dept. of Energy Small Business Forum and Expo held May 16-18, 2017 in Kansas City, Mo.

Rensselaer Polytechnic Institute President's Commencement Colloquy to Address "Criticality, Incisiveness, Creativity"

To kick off the Rensselaer Polytechnic Institute Commencement weekend, the annual President's Commencement Colloquy will take place on Friday, May 19, beginning at 3:30 p.m. The discussion, titled "Criticality, Incisiveness, Creativity," will include the Honorable Ernest J. Moniz, former Secretary of Energy, and the Honorable Roger W. Ferguson Jr., President and CEO of TIAA, and will be moderated by Rensselaer President Shirley Ann Jackson.

ORNL, University of Tennessee Launch New Doctoral Program in Data Science

The Tennessee Higher Education Commission has approved a new doctoral program in data science and engineering as part of the Bredesen Center for Interdisciplinary Research and Graduate Education.

SurfTec Receives $1.2 Million Energy Award to Develop Novel Coating

The Department of Energy has awarded $1.2 million to SurfTec LLC, a company affiliated with the U of A Technology Development Foundation, to continue developing a nanoparticle-based coating to replace lead-based journal bearings in the next generation of electric machines.

Ames Laboratory Scientist Inducted Into National Inventors Hall of Fame

Iver Anderson, senior metallurgist at Ames Laboratory, has been inducted into the National Inventors Hall of Fame.

DOE HPC4Mfg Program Funds 13 New Projects to Improve U.S. Energy Technologies Through High Performance Computing

A U.S. Department of Energy (DOE) program designed to spur the use of high performance supercomputers to advance U.S. manufacturing is funding 13 new industry projects for a total of $3.9 million.

Penn State Wind Energy Club Breezes to Victory in Collegiate Wind Competition

The Penn State Wind Energy Club breezed through the field at the U.S. Department of Energy Collegiate Wind Competition 2017 Technical Challenge, held April 20-22 at the National Wind Technology Center near Boulder, Colorado--earning its third overall victory in four years at the Collegiate Wind Competition.


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Casting a Wide Net

Designed molecules will provide positive impacts in energy production by selectively removing unwanted ions from complex solutions.

New Software Tools Streamline DNA Sequence Design-and-Build Process

Enhanced software tools will accelerate gene discovery and characterization, vital for new forms of fuel production.

The Ultrafast Interplay Between Molecules and Materials

Computer calculations by the Center for Solar Fuels, an Energy Frontier Research Center, shed light on nebulous interactions in semiconductors relevant to dye-sensitized solar cells.

Supercapacitors: WOODn't That Be Nice

Researchers at Nanostructures for Electrical Energy Storage, an Energy Frontier Research Center, take advantage of nature-made materials and structure for energy storage research.

Groundwater Flow Is Key for Modeling the Global Water Cycle

Water table depth and groundwater flow are vital to understanding the amount of water that plants transmit to the atmosphere.

Finding the Correct Path

A new computational technique greatly simplifies the complex reaction networks common to catalysis and combustion fields.

Opening Efficient Routes to Everyday Plastics

A new material from the Inorganometallic Catalyst Design Center, an Energy Frontier Research Center, facilitates the production of key industrial supplies.

Fight to the Top: Silver and Gold Compete for the Surface of a Bimetallic Solid

It's the classic plot of a buddy movie. Two struggling bodies team up to drive the plot and do good together. That same idea, when it comes to metals, could help scientists solve a big problem: the amount of energy consumed by making chemicals.

Saving Energy Through Light Control

New materials, designed by researchers at the Center for Excitonics, an Energy Frontier Research Center, can reduce energy consumption with the flip of a switch.

Teaching Perovskites to Swim

Scientists at the ANSER Energy Frontier Research Center designed a two-component layer protects a sunlight-harvesting device from water and heat.


Saving Energy Through Light Control

Article ID: 673922

Released: 2017-05-01 18:05:56

Source Newsroom: Department of Energy, Office of Science

  • Credit: Image: Manuel A. Ortuño, ICDC EFRC

    Change of a metal-organic framework (honeycomb) from transparent to opaque upon an electric current.

  • Credit: Image: Nathan Johnson, Pacific Northwest National Lab

    A porous material, with a honeycomb-esque structure, quickly changes from transparent to opaque when it meets an electrical current.

Tired of inconvenient blinds and shades? Switch to smart glass, windows that get dark on bright days and turn clear on cloudy ones. Researchers at the Center for Excitonics took advantage of the fundamental properties of molecules to design a material that changes from transparent to opaque (and vice versa) within only a few seconds.

If someone asks you which sector of modern American life is the most energy demanding, what would you say? Industry? Transportation, maybe? Well, not quite. According to the Energy Information Administration, in 2015, residential and commercial buildings consumed half of all the energy produced in the United States. Making our neighborhoods comfortable costs us a lot of energy, but the proper control of sunlight can drastically reduce heating and cooling costs. Along these lines, the versatile chemical composition and high porosity of metal-organic frameworks (MOFs for short) make them suitable for a broad variety of applications.

Metal-organic frameworks are sponge-like, porous materials formed by an extended network of metallic centers (nodes) tied together with organic molecules (linkers). The MOF used in this study resembles a honeycomb as shown in the figure, where the hexagon vertices are nodes and the edges are linkers. Both components are key to the success of the material.

No more blinds. There is a particular family of molecules that can change color under an applied electric current. Based on that idea, the researchers prepared a MOF using one of those color-changing molecules as the linker. The new design worked nicely. With an applied voltage, the MOF transitioned from transparent to opaque and vice versa, as shown in the figure.

But wait, here is where the unique nature of MOFs really pays off. While other compounds need several minutes to change color, the MOF only takes a few seconds. The high efficiency comes from its sponge-like structure, which allows a fast movement of charged species within the pores of the material.

Before throwing all your blinds and shades away, we first need to apply a MOF coating on glass to further develop smart window applications. Now the other component of the MOF — the metallic node — enters into play. The researchers found that the MOF with nickel nodes adhered to glass faster than its magnesium counterpart. The rapid growth produces a smooth, thin film on glass that greatly improves the optical properties of the nickel-based material.

Clear sight to the future of energy savings. This study demonstrates the potential of MOFs as energy-efficient materials. The fast and nearly complete transition from transparent to dark holds promise to design new technologies for elevators, screen projectors, aircrafts, and trains. To paraphrase the old saying: In the country of blinds, MOFs are the new kings.

Acknowledgments: 

Fundamental studies of opto-electronic properties of MOFs were supported by the Center for Excitonics, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Translational support for developing smart windows from color-changing MOFs was provided by a cooperative agreement between the Masdar Institute of Science and Technology (Abu Dhabi) and the Massachusetts Institute of Technology. K.A. acknowledges Saudi Aramco for financial support during graduate studies.

More Information: 

AlKaabi K, CR Wade, and M Dincӑ. 2016. “Transparent-to-Dark Electrochromic Behavior in Naphthalene-Diimide-Based Mesoporous MOF-74 Analogs.” Chem 1(2):264-272. DOI: 10.1016/j.chempr.2016.06.013

This item, written by Manuel A. Ortuno, is part of Frontiers in Energy Research, a newsletter for the Energy Frontier Research Centers created by early career members of the centers. See http://www.energyfrontier.us/newsletter/